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1582 Uppsatser om Soil water - Sida 10 av 106

Vilken preferens har tjockskalig målarmussla (Unio crassus) för bottensubstrat och vattenhastighet i Storån, Östergötland?

The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.

Identifiering av fosfatfosfors käll- och flödesfördelning i ett litet jordbruksområde

Eutrophication of lakes and streams are nowadays a well known environmental problem and implies an enrichment of the nutrients phosphorus (P) and nitrogen (N). Phosphorus is considered to be the most important component for the growth of aquatic plants and leads in too large quantities to an intensification of growth. Phosphate (PO4) is the fraction of phosphorus that can easiest be taken up by plants and thus have the greatest impact on eutrophication. Increased plant growth in lakes and unfavorable conditions for aquatic animals are two examples of negative consequences. A significant portion of the increased nutrient supply to nearby water can be derived to phosphate leaching from agricultural areas, where private sewers and agriculture is two main sources.

Sönderdelning av plogtilta med skärknivar :

During the last couple of years it has been more important to reduce the driving on the field to prepair the soil after ploughing. The machine costs are high so it is necessary to be effective. To reach a pleasant soilbed directly after ploughing is sometimes possible on easier soils but heavier clay soils always need more tillages. There is a lot of equipment mounted on the ploughs on the market, for example Furrow Cracker and Furrow presses, which makes a pleasant soilbed on easier soils. The last year Överum and Kverneland have presented knives which are mounted on the wing or moulboard.

Miljöteknisk undersökning enligt MIFO : en studie på fastigheten Bodsjölandet 1:14 avseende den nedlagda tjärfabriken i Grötingen

During 40 years of industrial production, from the end of the 1890?s until the end of 1930?s, coal and wood distillation products were manufactured in AB Carbo?s tar factory along the River Gimån in Grötingen, in the county of Jämtland, Sweden. In accordance with the Swedish Environmental Protection Agency?s Methods for Inventories of contaminated sites, MIFO, the site in Grötingen has been identified as a potentially contaminated site. In order to determine whether toxic substances pose a threat to human health and ecological systems in the area, there was a need to investigate the presence of contaminants, their levels and potential for migration.

Hållbar vattenförsörjning i områden med vattenbrist : Sustainable water supply solutions for areas affected by water shortage

In some coastal areas in Sweden water shortage sometimes appears because the withdrawal of groundwater is greater than the groundwater recharge. It creates a situation where the available groundwater is insufficient to support residents and businesses with drinking water. The high withdrawal of groundwater also creates a risk for saltwater intrusion to drinking water wells. The problem most commonly occurs during the summer when the groundwater recharge is low, but the population is high, due to tourism and summer residents.The purpose of this study was to investigate how local water supply in areas affected by water shortage can be solved as sustainable as possible. The work was divided into three parts where the first part comprised of a literature review on water systems in which four different options were investigated: artificial groundwater recharge, rainwater harvesting, desalination and water reuse.

EU:s medborgarinitiativ : En framkomlig väg för att minska det demokratisk underskottet?

The European Union is struggling to maintain democracy and tries to increase the participation among the citizens in Europe. The European Citizens? Initiative, ECI, is a platform established by the European Commission to allow citizens to propose new legislation. ?Water and sanitation are a human right! Water is a public good, not a commodity!? is the first ECI that has met the requirements.

?R KUSTN?RA ALK?RR I BOHUSL?N ETT ?BLUE CARBON? HABITAT?

In coastal wetlands carbon/organic matter can be stored for long periods of time thanks to, among other things, the presence of water which slows down the decomposition. Because of this, restauration and management of such habitats have the potential to decrease the emission of greenhouse gasses and help mitigate climate. Internationally these environments are called ?blue carbon? ecosystems. In Sweden, alder (Alnus glutinosa and Alnus incanata) covered wetlands along the coast is a nature type that potentially could function as a ?blue carbon? habitat.

Sjunkande pH i Västerbottens humuslager : en kvantitativ analys

Acidification is a central concept in the environmental debate. The effect of acidification of the soil is a matter of a decreasing amount of cations and thereby a decreasing ability to resist a supply of hydrogen ions to the soil. Acidification has gradually increased in the O horizon in Västerbotten over a 30-year period from the 1970th to the 1990th. The aim of this study was from inventories of The Swedish National Forest Soil Survey and The Swedish National Forest Inventory explain and quantify the acidification that has occurred in the O horizon of two regions in the north of Sweden. Data from SMHI, The Swedish Meteorological and Hydrological Institute, has also been used.

3D-visualisering i markprojekteringsprocessen

The thesis has been made for NCC Teknik in Gothenburg. The NCC Corporation is one of the largest leading companies in Scandinavia within the construction industry. NCC is active throughout the whole construction process, where one part is to carry out soil investigations prior the construction of various buildings, for example residential buildings. NCC Technology wants to visualize the samples taken at the construction sites in 3D for clients, authorities and also internally to show in a simple and understandable way how contamination is spread out in the soil.The thesis includes the area of Limhamns läge in Malmö, previously an industrial area. The area has previously included a concrete factory and the contamination from that factory has lingered in the soil.

Små vatten- och avloppssystem : Möjligheter till inskränkning av verksamhtesområden

This study is focused on small scale water and wastewater handling in Sweden. The study is divided into two major parts; the first describes common methods for water- and wastewater handling and the second part is a case study on three small and expensive systems in Gällivare municipality, in the north of Sweden. In the case study, abilitys for the local government to hand over unwanted systems to the water users is investigated and found to be a plausible solution to cut costs for two out of the three studied systems. In the third case, water and wastewater systems is not recommended to be handed over but other ways of cutting costs are suggested..

Kväveomsättning i gräsmark med olika artantal och artsammansättningar :

This study was carried out at the Swedish University of Agricultural Sciences, Dept. of Agricultural Research for Northern Sweden. The aim of the study was to determine how plant species richness and diversity influence the nitrogen pools and nitrogen fluxes in the soil. Plant and soil samples from a biodiversity experiment in grasslands were used. Thirty plots with 12 grassland plant species (legumes, grasses, and non-legume herbs), combined from 1-12 species were investigated.

Skydd mot yterosion i slänter av finmorän

Slopes in fine till soils are exposed to surface erosion due to rainfall, snowmelt and upland water sources. Large areas of road slopes are therefore covered for surface erosion protection. Preventive methods like ditches and trenches are also being used. Silt tills are particularly troublesome since the water can bring the soil into suspension and cause mudslides. Different methods for erosion protection have been studied in this work, with the emphasis placed on rockfill covering. The need for and the dimensioning of this type of covering has been examined in literature and field studies.

Rekonstruktion av jordartsförhållanden i Ingarvet, Falun, från geotekniska rapporter

The Falun area has been undergoing mining activity for a very long time and miningslag piled up and was used as foundations for building houses and roads, Ingarvetstarted expanding in the 1970s to an industrial area. The main goal for this report is toreconstruct a soil map of how the landscape was before anthropogenic effects. With thehelp of ArcGIS and geotechnical reports a soil map for parts of Ingarvet, Falun werecreated..

Brunnsviken : Utvärdering av åtgärder för förbättrad vattenkvalitet

Periods of hypoxia are a recurring issue in Brunnsviken. Main factors that trigger hypoxia in Brunnsviken are eutrophication  due to anthropogenic emission of nutrients, stratification in the water column due to salinity and temperature differences  that prevents mixing and a sill inlet that prevents water exchange. As an attempt to improve the oxygen levels, bottom water is pumped from Brunnsviken causing aerated surface water to flow back into the basin.  The objective of this Master?s thesis was to study the change in dissolved oxygen levels due to pumping.

Dimensionering av betongplatta på lös undergrund. En jämförelse mellan tre beräkningsprogram

Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.

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